We propose the study of visibly pushdown automata (Vpa) for processing XML documents. Vpas are pushdown automata where the input determines the stack operation, and XML documents ...
The paper investigates the question of whether a partially closed database has complete information to answer a query. In practice an enterprise often maintains master data Dm, a ...
Given a huge real graph, how can we derive a representative sample? There are many known algorithms to compute interesting measures (shortest paths, centrality, betweenness, etc.)...
Estimating the result size of complex queries that involve selection on multiple attributes and the join of several relations is a difficult but fundamental task in database query...
Geometric coordinates are an integral part of many data streams. Examples include sensor locations in environmental monitoring, vehicle locations in traffic monitoring or battlefi...